{"id":4706,"date":"2022-02-08T10:16:31","date_gmt":"2022-02-08T15:16:31","guid":{"rendered":"https:\/\/cecas.clemson.edu\/ideas\/?p=4706"},"modified":"2022-03-15T11:18:54","modified_gmt":"2022-03-15T15:18:54","slug":"positive-energy","status":"publish","type":"post","link":"https:\/\/cecas.clemson.edu\/ideas\/positive-energy\/","title":{"rendered":"Positive Energy"},"content":{"rendered":"

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Positive Energy<\/h1><\/div><\/div><\/div>

Positive Energy<\/h1><\/div><\/div><\/div>

Positive Energy<\/h1><\/div><\/div><\/div>

Brian Powell and his team play a key role in maintaining a sustainable environment<\/p>\n<\/div><\/div><\/div>

Brian Powell and his team play a key role in maintaining a sustainable environment<\/p>\n<\/div><\/div><\/div><\/div><\/div>

Brian Powell of Clemson University and his team are working to make sure nuclear waste is safely and securely managed. Their research is focused on spent fuel from nuclear power plants, as well as defense-related waste.<\/p>\n

Photo: Brian Powell, Fjeld Professor in Nuclear Environmental Engineering and Science, works in a lab with students.<\/em><\/p>\n<\/div><\/div><\/div><\/div><\/div>

Brian Powell of Clemson University and his team are working to make sure nuclear waste is safely and securely managed. Their research is focused on spent fuel from nuclear power plants, as well as defense-related waste.<\/p>\n

Photo: Brian Powell, Fjeld Professor in Nuclear Environmental Engineering and Science, works in a lab with students.<\/em><\/p>\n<\/div><\/div><\/div><\/div><\/div>

It\u2019s a crucial issue in South Carolina and nationwide because nuclear energy is a major source of power. Also, millions of gallons of defense-related nuclear waste are awaiting treatment and disposal at U.S. Department of Energy facilities across the country.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

It\u2019s a crucial issue in South Carolina and nationwide because nuclear energy is a major source of power. Also, millions of gallons of defense-related nuclear waste are awaiting treatment and disposal at U.S. Department of Energy facilities across the country.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

19.7% of U.S. electricity generation comes from nuclear generation. Source:<\/strong> U.S. Energy Information Administration <\/a><\/p>\n<\/div><\/div><\/div><\/div><\/div>

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19.7% of U.S. electricity generation comes from nuclear generation. Source:<\/strong> U.S. Energy Information Administration <\/a><\/p>\n<\/div><\/div><\/div><\/div><\/div>

South Carolina\u2019s four nuclear power plants supplied more than half its energy as recently as 2020. Source:<\/strong> U.S. Energy Information Administration<\/a><\/p>\n<\/div><\/div><\/div><\/div><\/div>

South Carolina\u2019s four nuclear power plants supplied more than half its energy as recently as 2020. Source:<\/strong> U.S. Energy Information Administration<\/a><\/p>\n<\/div><\/div><\/div>

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The U.S. Department of Energy\u2019s Office of Environmental Management manages a large amount of legacy wastes from nuclear weapons production. Its budget request was nearly $7.6 billion for fiscal year 2022 alone. Source:<\/strong> Energy.gov<\/a><\/p>\n<\/div><\/div><\/div><\/div><\/div>

The U.S. Department of Energy\u2019s Office of Environmental Management manages a large amount of legacy wastes from nuclear weapons production. Its budget request was nearly $7.6 billion for fiscal year 2022 alone. Source:<\/strong> Energy.gov<\/a><\/p>\n<\/div><\/div><\/div>

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Some of the Powell team\u2019s most recent published work has focused on nuclear-power plant waste, particularly neptunium. Power plant operators store spent nuclear fuel in pools and dry casks, but those locations are not intended as permanent homes. Rather, radioactive waste will need to be stored underground in geologically stable sites for hundreds of thousands of years. To ensure environmental safety, it is important to understand how waste transforms chemically\u2013 and that\u2019s why the Powell team\u2019s work is so important. Source:<\/strong> U.S. Department of Energy Office of Science<\/a><\/p>\n<\/div><\/div><\/div><\/div><\/div>

Some of the Powell team\u2019s most recent published work has focused on nuclear-power plant waste, particularly neptunium. Power plant operators store spent nuclear fuel in pools and dry casks, but those locations are not intended as permanent homes. Rather, radioactive waste will need to be stored underground in geologically stable sites for hundreds of thousands of years. To ensure environmental safety, it is important to understand how waste transforms chemically– and that\u2019s why the Powell team\u2019s work is so important. Source:<\/strong> U.S. Department of Energy Office of Science<\/a><\/p>\n<\/div><\/div><\/div>

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To understand where neptunium comes from, you have to start with uranium. The heavy metal splits in a nuclear reactor to generate heat, which produces steam to spin a generator, creating electricity. But not all the uranium splits. Instead, some of it gets heavier and becomes neptunium or plutonium. Both are particularly toxic, making safe disposal absolutely critical.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

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To understand where neptunium comes from, you have to start with uranium. The heavy metal splits in a nuclear reactor to generate heat, which produces steam to spin a generator, creating electricity. But not all the uranium splits. Instead, some of it gets heavier and becomes neptunium or plutonium. Both are particularly toxic, making safe disposal absolutely critical.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

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Fortunately, the toxic elements can be turned into neptunium oxide or plutonium oxide, which makes them more stable for long-term storage or disposal. Both remain solid and not easily dissolved by water as long as they stay in oxide form.<\/p>\n<\/div>

*Not actual photo. Interpretive illustration.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

Fortunately, the toxic elements can be turned into neptunium oxide or plutonium oxide, which makes them more stable for long-term storage or disposal. Both remain solid and not easily dissolved by water as long as they stay in oxide form.<\/p>\n<\/div>

*Not actual photo. Interpretive illustration.<\/p>\n<\/div><\/div><\/div>

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However, previous research has shown that neptunium under common environmental conditions can undergo a chemical reaction that makes it more easily dissolved. If the waste is buried and hit by rainwater that trickles through the soil, it could become mobile, raising the risk it could escape the storage site and pollute the environment.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

However, previous research has shown that neptunium under common environmental conditions can undergo a chemical reaction that makes it more easily dissolved. If the waste is buried and hit by rainwater that trickles through the soil, it could become mobile, raising the risk it could escape the storage site and pollute the environment.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

One of Powell\u2019s former Ph.D. students, Kathryn Peruski, focused her dissertation on what to do about neptunium. She co-authored two papers, both published in the journal Environmental Science: Nano<\/em> and featured on the U.S. Department of Energy Office of Science website.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

One of Powell\u2019s former Ph.D. students, Kathryn Peruski, focused her dissertation on what to do about neptunium. She co-authored two papers, both published in the journal Environmental Science: Nano<\/em> and featured on the U.S. Department of Energy Office of Science website.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

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While the neptunium appears solid to the human eye, a closer look through an electron microscope reveals that it is made of billions of particles, or grains (top left image). Peruski found that the chemistry that causes neptunium to dissolve happens where the grains meet. Those areas are called grain boundaries (bottom image). Peruski also discovered it is possible for a single particle to break off, which raises the risk it could move through the soil with the rainwater and escape the storage site.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

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While the neptunium appears solid to the human eye, a closer look through an electron microscope reveals that it is made of billions of particles, or grains (top left image). Peruski found that the chemistry that causes neptunium to dissolve happens where the grains meet. Those areas are called grain boundaries (bottom image). Peruski also discovered it is possible for a single particle to break off, which raises the risk it could move through the soil with the rainwater and escape the storage site.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

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The good news is that Peruski also found a potential solution. To make neptunium oxide, neptunium is combined with chemicals and heated in a furnace. Peruski found that when the neptunium mixture was heated at 900 degrees centigrade, the grains came out 500 times larger than when it was heated at 400 degrees centigrade. Larger grains resulted in fewer boundaries and therefore a more stable material.<\/p>\n

That means it could be possible to bury more neptunium oxide in the same site if the material is formed with high heat.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

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The good news is that Peruski also found a potential solution. To make neptunium oxide, neptunium is combined with chemicals and heated in a furnace. Peruski found that when the neptunium mixture was heated at 900 degrees centigrade, the grains came out 500 times larger than when it was heated at 400 degrees centigrade. Larger grains resulted in fewer boundaries and therefore a more stable material.<\/p>\n

That means it could be possible to bury more neptunium oxide in the same site if the material is formed with high heat.<\/p>\n<\/div><\/div><\/div><\/div><\/div>